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Discussion Starter · #1 ·
i currently have lt4 heads on my imp and i'm looking for more power in the near future(aren't we all). so i was planing on stayin with the cam i have but sending my lt4's out to be ported, probally LE. but while doin some searching i found that some people think ported lt1's are better then ported lt4's??? i don't understand, to me it seems that if the stock lt4's are better to start with then with the same port work they will be better also. any advice or insite into this is appercated. btw i'm talkin about alum f-body heads not iron b-bodys
harold
 
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Discussion Starter · #2 ·
Originally posted by mess21:
......while doin some searching i found that some people think ported lt1's are better then ported lt4's......
Ported LT1 heads are better for some applications than LT4....or ported LT4 heads.

If you have a 350 and you're looking for more power naturally aspirated I'd look into selling the LT4 gear and using the funds for a ported LT1 set-up.....as a start. Or......you could leave the LT4 heads and look to other ways to build power.

I'm becoming part of the camp that believes that the LT4 heads in B-bodies are better suited to strokers or blown applications. It's not that the LT4 set-up can't be made to work and work well......but the ported LT1 heads may be a better route for a stock bottom end.

KW
 
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Discussion Starter · #3 ·
Well, I had ported LT1 aluminum heads on my 385 stroker motor, and I now have ported LT4 heads on my new 409 stroker motor. Let's just say, for my application, the ported LT4's are the way to go. :cool:

If you gave me a choice between ported, aluminum LT1 heads, and ported LT4 heads, I would choose the LT4 heads. Of course, how well either head is ported is a variable, just like cam selection, stall, and gears.

I think, with the right setup, LT4's are the way to go. I'm not a cam or head expert, but I've got lots of track time, with lot's of different setups. ;)
 
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Discussion Starter · #4 ·
LT4 heads have too big of a port crossectional area for most LT1s with a stock stroke that rev below 7000 rpms. This causes the car to be lazy at lower rpms.

A bigger displacement engine needs a bigger port, valves, MCA, etc. That's why LT4 heads work well with a stroker. LT1 heads are going to choke a stroker at 6000+ rpms unless MAJOR work (read: welding) has been done to them.
 
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